Dating gold filled
From: The Essential Guide to the US Trade in Gold or Silver Jewelry. Here are some great quotes from Artisan on the difference between gold plating, gold filled/gold overlay: “The most important difference is layer thickness.Depletion Gilding from the archaeological site: Sitio Conte in Panama. Items designated as “gold filled” can be up to 200 times thicker than the heaviest gold electroplating…” “Gold filled items are created by using heat and pressure to permanently fuse a layer of karat gold over a less costly base metal…” “Gold electroplating, especially with the advent of super hard plating materials, are widely used on designs which have intricate or complex shapes.” The following list is organized by: quality in DESCENDING order with number 9 being the thinnest application and 1 the heaviest application of gold.Longines Flagship 10 carat gold filled gentlemans' calendar watch dating to 1966.In great original un-restored condition, the case and dial present very well and the manual movement is running strongly and keeping time.The following article is from my Newsletter: In the Studio with Nancy, Volume 3 (sign up on my home page).
The watch is in excellent overall condition, with an elegant classic case, original and unrestored art-deco style dial with a sweep seconds hand and centre dial alarm.
The first date codes, found for example on the Vacumatics, consists of two digits, the first one denoting the quarter of production, the second denoting the production year.
In mid 1934 Parker began marking most pens and pencils with a date code, both the barrel and the nibs were marked, but lacking a date code doesn't necessarily mean that the pen was made pre-1935, since many imprints have been worn off with use.
Alloys of copper with gold and some silver were employed, known as tumbaga.
Gold plating of silver is used in the manufacture of jewelry.